Embedment Strain Gauges

An embedment strain gauge is essentially a vibrating wire sensor sealed inside a steel body, placed in fresh concrete before it sets. As the structure cures and later takes load, the wire’s tension shifts in response to strain. That frequency is read by a portable logger or an automatic system. Kingmach gauges use a proven vibrating wire principle, with stainless steel construction that resists corrosion in wet, alkaline environments. Standard models can be produced with active gauge lengths from 150 mm to 300 mm, but longer or shorter versions are possible for different aggregate sizes or research setups. The end blocks anchor the gauge firmly in the concrete, minimizing slip. Temperature change is also tracked—each unit includes a thermistor, so strain data can be corrected. Typical accuracy runs around ±0.1% of full scale, with ranges commonly from 3000 to 4000 microstrain. These aren’t lab-only numbers; they come from factory calibration across the full working range. Installation is straightforward if planned early. The gauge is tied to rebar or a mounting frame before pouring, and the cable is routed to a junction box. For mass concrete, multiple gauges can be arranged in rosettes to capture strain in several directions. Kingmach ships gauges with rugged polyurethane-jacketed cables that handle construction site handling. For long-term jobs, stainless steel cable armor is an option. After-sales, replacement calibration factors or spares can be sent through existing distribution partners in Latin America, Southeast Asia, and parts of Africa. Tech support is part of the offer—questions about grout compatibility or cable splicing get answered by engineers who have done this themselves. If a project has unusual conditions, like high radiation (as in nuclear containment) or dynamic loading, a custom design is usually feasible with a few extra weeks of lead time.